The present invention relates to a key input means which itself indicates an input condition and, more particularly, to a key input means having a switching element made of a light emitting diode.
A conventional mechanical switch of the depression type can be associated with a lamp so as to indicate a switching condition of the mechanical switch, or, to indicate the depression operation effected to the mechanical switch. However, the above-mentioned mechanical switch requires a large space and, therefore, such a mechanical switch is not suited for a keyboard means including a large number of switching elements aligned thereon. Moreover, the above-mentioned mechanical switch is not suited for rapid operation, because the mechanical switch requires a considerably long operation stroke to ensure stable operation.
Accordingly, an object of the present invention is to provide a key input means which itself indicates an input condition.
Another object of the present invention is to provide a key input means suited for a keyboard means which can indicate the switching condition of the respective switching elements.
Still another object of the present invention is to provide a key input means suited for rapid operation.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
To achieve the above objects, pursuant to an embodiment of the present invention, a metal casing of a light emitting diode is electrically connected to the cathode electrode of the light emitting diode. A detection means is provided for detecting the touch operation of the operator to the metal casing of the light emitting diode, thereby developing a key input signal. A driver is further provided to enable the light emitting diode in response to the output signal, or, the key input signal derived from the detection means.